Establishment and evaluation of fast predictive algorithm for urinary tract infection pathogen in patients with nephrolithiasis

doi:10.3969/j.issn.1673-8640.2021.01.015

Abstract

Abstract:

Objective To establish an algorithm that can predict potential pathogens causing urinary tract infection（UTI）based on routine urinalysis in nephrolithiasis patients. Methods A total of 414 clean-catch urine specimens of nephrolithiasis patients were collected. The comparison between flow cytometry count,nitrite,leukocyte esterase and urine culture was undertaken to assess the optimal cut-off value for predictive algorithm. Results The cut-off value of flow cytometry bacterial count was 231.8/μL（sensitivity 73.97%,specificity 91.14%）. Furthermore,the samples with nitrite positive（OR=7.789,95%CI: 3.304-18.358,P<0.000 1） and/or leukocyte esterase 4+（OR=2.738,95%CI: 1.358-5.519,P=0.004 9） were more likely to contain Gram negative bacteria. Conclusion A fast predictive algorithmusing the combination of urine dipstick and flow cytometry can predict the infection of Gram-positive bacteria and Gram-negative bacteria in nephrolithiasis patientsand has certain clinical value.

Key words: Nephrolithiasis, Urinary tract infection, Flow cytometry, Urine dipstick

CLC Number:

R446.5

XIAO Nan, ZHOU Jia, DUAN Ning, ZHU Tianyang, WANG Lijun. Establishment and evaluation of fast predictive algorithm for urinary tract infection pathogen in patients with nephrolithiasis[J]. Laboratory Medicine, 2021, 36(1): 75-79.

Figures/Tables 6

References 13

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尿培养结果	例数	亚硝酸盐/例		白细胞酯酶/例					细菌计数中位数/µL	白细胞计数中位数 /（个/µL）
尿培养结果	例数	阴性	阳性	阴性	1+	2+	3+	4+	细菌计数中位数/µL	白细胞计数中位数 /（个/µL）
阴性	268	266^*	2^*	145^*	29^*	27^*	17^*	50^*	18.243	16.5
阳性	146	84	62	28	4	7	16	91	1 328.200	378.8
合计	414	350	64	173	33	34	33	141

尿培养结果	例数	亚硝酸盐/例		白细胞酯酶/例					细菌计数中位数/µL	白细胞计数中位数 /（个/µL）
尿培养结果	例数	阴性	阳性	阴性	1+	2+	3+	4+	细菌计数中位数/µL	白细胞计数中位数 /（个/µL）
阴性	268	266^*	2^*	145^*	29^*	27^*	17^*	50^*	18.243	16.5
阳性	146	84	62	28	4	7	16	91	1 328.200	378.8
合计	414	350	64	173	33	34	33	141

检测项目	阈值	敏感性/%	特异性/%	OR值（95%CI）	AUC（95%CI）
细菌计数	231.8 /µL	73.97	91.14	28.80（13.41~44.09）	0.871（0.835~0.902）
白细胞计数	139.8个/µL	69.18	78.60	8.28（3.67~12.89）	0.777（0.734~0.816）
亚硝酸盐	+	42.47	99.25	97.74（24.82~170.66）
白细胞酯酶	+	83.56	54.10	6.10（1.37~10.83）

检测项目	阈值	敏感性/%	特异性/%	OR值（95%CI）	AUC（95%CI）
细菌计数	231.8 /µL	73.97	91.14	28.80（13.41~44.09）	0.871（0.835~0.902）
白细胞计数	139.8个/µL	69.18	78.60	8.28（3.67~12.89）	0.777（0.734~0.816）
亚硝酸盐	+	42.47	99.25	97.74（24.82~170.66）
白细胞酯酶	+	83.56	54.10	6.10（1.37~10.83）

组别	例数	白细胞酯酶					亚硝酸盐		细菌计数/µL	白细胞计数/（个/µL）
组别	例数	阴性/例	1+/例	2+/例	3+/例	4+/例	阴性/例	阳性/例	细菌计数/µL	白细胞计数/（个/µL）
革兰阳性菌组	53	16	2	2	8	25	45	8	398.6	196.6
革兰阴性菌组	93	12	2	5	8	66	39^*	54^*	5 866.5^***	541.2^*